$ git clone -n https://src.fedoraproject.org/rpms/perl-Chemistry-Pattern.git /var/lib/mock/f45-build-22283-590/root/chroot_tmpdir/scmroot/perl-Chemistry-Pattern
Cloning into '/var/lib/mock/f45-build-22283-590/root/chroot_tmpdir/scmroot/perl-Chemistry-Pattern'...
$ git fetch origin f7eb417567b4a614f1cc07a8488bee4c8d1a540c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Chemistry-Pattern
 * [new ref]         f7eb417567b4a614f1cc07a8488bee4c8d1a540c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f7eb417 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild